update

Update files or directories imported from external DVC repositories, and the corresponding import stage .dvc files.

Synopsis

usage: dvc update [-h] [-q | -v] [--rev <commit>] [-R]
                  targets [targets ...]

positional arguments:
  targets      Import stage .dvc files to update. Using -R, directories
               to search for .dvc files can also be given.

Description

After creating import stages (.dvc files) with dvc import or dvc import-url, the data source can change. Use dvc update to bring these imported file or directory up to date.

To indicate which import stages to update, we can specify the corresponding .dvc file targets as command arguments.

Note that import stages are considered always frozen, meaning that if you run dvc repro, they won't be updated. dvc update is the only command that can update them.

dvc update without flags will not have an effect on import stages that are fixed to a commit hash (rev field in the .dvc file). Use the --rev option to update an imported artifact to a different revision.

$ dvc update --rev master

Options

--rev <commit> - commit hash, branch or tag name, etc. (any Git revision) of the repository to update the file or directory from. The latest commit in master (tip of the default branch) is used by default when this option is not specified.

Note that this changes the rev field in the import stage, fixing it to the revision.
-R, --recursive - determines the files to update by searching each target directory and its subdirectories for import stage .dvc files to inspect. If there are no directories among the targets, this option is ignored.
-h, --help - prints the usage/help message, and exit.
-q, --quiet - do not write anything to standard output. Exit with 0 if no problems arise, otherwise 1.
-v, --verbose - displays detailed tracing information.

Example

Let's first import a data artifact from our get started example repo:

$ dvc import git@github.com:iterative/example-get-started model.pkl
Importing 'model.pkl (git@github.com:iterative/example-get-started)'
-> 'model.pkl'

As DVC mentions, the import stage (.dvc file) model.pkl.dvc is created. This stage file is frozen by default though, so to reproduce it, we would need to run dvc unfreeze on it first, then dvc repro (and dvc freeze again). Let's just run dvc update on it instead:

$ dvc update model.pkl.dvc
Output 'model.pkl' didn't change. Skipping saving.
Saving information to 'model.pkl.dvc'.

This time nothing has changed, since the source project is rather stable.

Note that dvc update updates the rev_lock field of the corresponding .dvc file (when there are changes to bring in).

Example: Updating fixed revisions to a different version

See also Importing and updating fixed revisions.

Let's import a model from a specific version of our get started example repo first:

$ dvc import --rev baseline-experiment \
            git@github.com:iterative/example-get-started \
            model.pkl
Importing 'model.pkl (git@github.com:iterative/example-get-started)'
-> 'model.pkl'

After this, the import stage (.dvc file) model.pkl.dvc is created. Let's try to run dvc update on the given stage file, and see what happens.

$ dvc update model.pkl.dvc

There was no output at all, meaning, the model.pkl file was not updated. This is because we tied the import stage to a rev that hasn't changed (i.e.baseline-experiment tag points to a specific Git commit). Therefore, it was not updated.

Let's try to update the model to a different version:

$ dvc update --rev bigrams-experiment model.pkl.dvc
Importing 'model.pkl (git@github.com:iterative/example-get-started)'
-> 'model.pkl'